public async Task <ImmutableArray <TextChange> > GetFormattingChangesAsync(
Document document,
TextSpan?textSpan,
CancellationToken cancellationToken)
{
var fallbackOptions = _globalOptions.GetCSharpSyntaxFormattingOptions();
var options = await _indentationManager.GetInferredFormattingOptionsAsync(document, fallbackOptions, explicitFormat : true, cancellationToken).ConfigureAwait(false);
var root = await document.GetRequiredSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
var span = textSpan ?? new TextSpan(0, root.FullSpan.Length);
var formattingSpan = CommonFormattingHelpers.GetFormattingSpan(root, span);
var services = document.Project.Solution.Workspace.Services;
return(Formatter.GetFormattedTextChanges(root, SpecializedCollections.SingletonEnumerable(formattingSpan), services, options, cancellationToken).ToImmutableArray());
}